Method of forming a nitride or carbonitride layer
CA 2048872 C · Owner: Takeda, Hiromasa · Inventors: Arai, Tohru; Nakanishi, Kazuyuki; Tachikawa, Hideo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A nitride or carbonitride layer is formed on the surface of a metal material as follows: A treating agent composed of a refractory powder of alumina or the like and a powder of a metal for forming a nitride or a carbide or an alloy thereof is disposed in a fluidized bed furnace; the treating agent is fluidized to form a fluidized bed by introducing an inert gas; the fluidized bed furnace is heated to a temperature of not higher than 700°C; an activator of a halogenated ammonium salt is intermittently supplied into the fluidized bed at a rate of 0.001 to 5 wt%/hour based on the total amount of the treating agent; and the metal material to be treated is disposed in the fluidized bed during or …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 9, 1991 and granted March 14, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 9, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 9, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.